Gas turbine engines, more particularly turbofan engines, comprises a fan case, an engine core, and an annular flow passage disposed therebetween. Vanes are typically used to reduce or increase the swirl in the air flow within the engine. The vanes may be individually radially insertable into corresponding slots in the case, at their desired location, such as inside the fan case within the annular gas flow passage.
To minimize air leakage between the inserted vane and the case, a grommet may be disposed between the surface of the case and the vane head. However, the grommet may deform, causing retention system relaxation due to elastomer compression set, which may then require field maintenance to tighten the retention system, such as a circumferential strap, holding the vanes to make sure vanes remain properly loaded.